The present invention relates generally to apparatus and methods that control dispensing of liquids, and more particularly, to an apparatus and method for precisely dispensing a controlled amount of liquid, such as epoxy, such as when it is applied to a surface of a manufactured component, for example.
Heretofore, control over the application of an epoxy or other liquid material, for example, to the surface of a printed wiring board to encapsulate or secure components thereon has been achieved by using a mass flow calibration method. The mass flow calibration method is based on a weight measurement of a sample of the epoxy. If the viscosity of the liquid epoxy changes, the dispensing apparatus automatically adjusts its dispensing parameters to dispense the desired volume of the liquid. The disadvantage of this method is that it uses indirect measurements, and it is insensitive to intermittent problems such as needle plugging or other hardware problems.
Therefore, there is a need for a reliable accurate method of providing control over the dispensing of a liquid, such as epoxy.
Accordingly, it is an objective of the present invention to provide for an apparatus and method for precisely dispensing a controlled amount of liquid. It is a further objective of the present invention to provide for an apparatus and method for precisely dispensing a liquid, such as epoxy, onto a surface of a component.